Conventionally, electric vehicles, such as electric automobiles and hybrid vehicles, are individually equipped with cooling circuits for various temperature ranges, which include, in addition to a circuit for engine cooling in a high-temperature range (approximately 100° C.), a circuit for cooling an inverter and a motor generator in an intermediate-temperature range (approximately 60° C.) and a circuit for cooling a battery pack in a low-temperature range (40° C.).
In this way, various cooling circuits are mounted on the vehicle, which can cause matters, such as a complicated configuration of the cooling circuits, or deterioration in mountability.
In electric vehicles or hybrid vehicles, when the vehicle interior is intended to be heated using waste heat from an engine or a power-train device as a heat source, the amount of heat is often insufficient, failing to adequately heat the interior.
As a countermeasure, vehicles with mounted heat pump cycles have also been developed. This technique can use the heat pump cycle to absorb heat from the outside air, thereby heating the vehicle interior. Such a technique, however, dissipates waste heat from the engine or power train device into the outside air without using the waste heat for heating, and thus has a problem of inefficient use of heat.
Patent Document 1 discloses a thermal controller for a vehicle that can switch and circulate the coolants for two systems in the motor generator and the inverter.